Governor construction



Jan. 6, 1948. J. L. MOODY GOVERNOR CONSTRUCTION Filed Oct. 4, 1943 ATTORNEY Patented Jan. 6, 1948 GOVERNOR CONSTRUCTION John L. Moody, Oakland, Calif., assignor to Friden Calculating Machine Co., Inc., a corporation of California Application October 4, 1943, Serial No. 504,977

10 Claims. (Cl. 200-80) This invention relates to governors for electric motors.

The object of my invention is to provide a governor having improved construction over that sgigzwn in my Patent 2,294,124, issued August 25.

In the drawings:

Figure 1 is anend view of a motor in which the governor of my invention has been installed.

Figure 2 is a side view with the governor parts in vertical section.

Figure 3 is a transverse section thru the governor on the line 3-3 of Figure 2.

Figure 4 is a transverse section on the line 4-4 in Figure 2.

The motor I has an armature shaft II on which a collar I3 is secured for rotation therewith by means of a set screw l4. Axially slidable with respect to the collar l3 and motor shaft II is a member I5 have a bearing portion I 6.

Means are provided for causing the bearing member to rotate with the collar but permitting axial movement thereof. This comprises a bracket l1 secured to the collar l3 at l8 which has fingers l9 and 20 (Fig. 4) formed thereon and disposed outwardly from the axis of the shaft I i. These fingers interfit with or are received in notches 2|, 22 (Fig. 3) formed at the outer ends of wing-like portions 23, 24 of the member l5. The-advantages of this construction are facility of manufacture and reduction of friction in the coupling. Notice that the drive is transmitted from the bracket I! to the bearing member l5 by the fingers I9, 20 engaging the sides of the notches 2|, 22. This arrangement not only employs a very small area where friction can occur, but has the additional advantage of increased leverage due to the distance of the fingers l9 from the axis of rotation 25.

Means responsive to centrifugal force are provided for causing axial movement of the bearing member I5. This comprises a lever 30 (Fig. 2) which is pivotally supported on a rod 3| secured in ears 32, 33 formed on the bracket ll. The lever 30 comprises a plate-like portion,35 which, as shown in Figure 2, is normally disposed substantially parallel to the axis of rotation. Depending from the pivotal portion of the lever are two forks 36, and 31, which as shown in Figure 3 engage the wing-like portions 23 and 24 of the bearing member 15. During rotation of the motor shaft the lever 30, under the infiuence of centrifugal force tends to rotate counter-clock- .wise (Fig. 2). Restraining this movement, however, is a broad leaf spring 40 which is shaped as best shown in Figure 4, where it will be noted that the spring has two apertures Al and 42 in which are received lugs 43, 44 formed integrally with the bracket H (see Fig. 2). These lugs act as a fulcrum for the spring 40. Projected inwardly from the fulcrum are finger portions 45. 4B which bear against the forks 36, 31. The outer end of the spring has an aperture through which a screw 41 passes. The screw 41 is threaded into an aperture in the collar I3 to permit adjustment thereof. A small coil spring 48 maintains the leaf spring 40 against the head of the screw 41. The screw 41 can be adjusted to vary the pressure which the spring 40 exerts on the lever 30.

The bearing member l5 which is moved axially in response to centrifugal force has a metal rod 50 rigidly mounted therein by means of an insulating bushing 5| so that the rod 50 rotates and moves axially in unison with the bearing member l5 and is electrically insulated therefrom by the bushing 5|. The rod 50 carries two movable contacts 52 and 53 which are annular in form and are supported co-axially with the axis of rotation by mounting collars 54, 55 adjustably secured to the rod 50 by set screws.

Arranged for cooperation with the movable contacts 52, 53 are fixed contacts 62, 63 respectively. These are also annular in form and arranged co-axlally with the axis of rotation. The contact 62 is secured at the end of a conductor strip 64 connected to a binding post 65. The contact 63 is secured to a conductor strip 66 which leads to a binding post 61. The binding posts 65, 61 are mounted in a bar of insulation 68 attached to posts 69, 10 on the motor. Conductors (not shown) connect the binding posts 65, 61 in the motor circuit in series.

The operation of the governor is as follows: when the speed of the motor shaft reaches a point at which centrifugal force exerted on the lever 30 overcomes the resistance of the spring 40, the forks 36, 31 move the bearing member I 5 axially to the right (Fig. 2) thereby causing the conductor rod 50 to be moved to the right, and resulting in the movable contacts 52, 53 being parted from the fixed contacts 62, 63 thus breaking the motor circuit.

The advantages of this construction over that of the governor disclosed in my patent previously mentioned are as follows: It was found that the Bakelite rod '21 (Fig. 2) of the patent, tends to warp and burn off due to the heat of the arcing of the contacts 34, 36. This was eliminated in my improved construction by mounting the contacts on a metal rod 50. 4 Another disadvantage of my previous construction was the corrodlng of the contacts 4|, 42. In that construction those contacts were not separated when the circuit was opened. In my improved construction I separate both pairs of contacts and have found that this eliminates the difficulty of corrosion.

The square member 26 (Figs. 2 and 4) of the patent tended to bind in the aperture provided for it in the bracket I8. This objection was overcome in the improved construction by employing the fingers i9, 20 to engage the notches 21, 22, the advantage of which construction was previously pointed out. It has also been found that the leaf spring employed in my improved con struction is more sensitive than the coil spring employed in the patent. This is due partly to the fact that in the improved construction the spring bears directly on the lever which reacts to centrifugal force, whereas in the patent the effect of the spring 48 has to be transmitted thru the lever 43, contacts 4|, 42, therod 21 and the block 26 to reach the lever 23 so that any change in the frictional resistance in these parts causes a change in the effective resistance of the spring 48 on the lever 23.

I claim:

1. A speed-responsive device for controlling the operation of an electric motor comprising, a lever pivotally supported on means secured to the motor shaft, said lever tending'to rotate on its pivotal axis under the influence of centrifugal force, a member having electric conductivity and mounted for movement axially of the motor shaft, motion transmitting means intermediate said lever and said member whereby pivotal movement of said lever causes axial movement of said member, two electrical contacts carried by said member for movement therewith, a relatively fixed contact for cooperation with each of said movable contacts and adapted to be connected in the motor circuit, whereby upon axial movement of said member in one direction said movable contacts will be engaged with said fixed contacts to establish the motor circuit and upon axial move ment of said member in the opposite direction said movable contacts will be parted from said fixed contacts to break the motor circuit.

2. A speed-responsive device for controlling the operation of an electric motor comprising, a member having electric conductivity, means for supporting said member for rotation with the motor shaft and for axial movement with respect thereto, means rotatable with the motor shaft and responsive to centrifugal force for imparting axial movement to said member, two contacts carried by said member, said contacts being axially movable with said member and rotatable therewith, two relatively fixed contacts for cooperation with said movable contacts whereby upon axial movement of said member the two movable contacts will be parted from the two fixed contacts to break the motor circuit.

3. A speed-responsive device for controlling the operation of an electric motor comprising, a metal rod, means to support said rod for rotation with the motor shaft and for axial movement with respect thereto, means rotatable with the motor shaft and responsive to centrifugal force for imparting axial roivement to said member, two annular contacts mounted on said rod for movement therewith, two relatively fixed annular contacts for cooperation with said movable contacts, said four annular contacts being disposed co- 4 axially with said rod whereby upon axial movement of said rod said movable contacts will be parted from said fixed contacts to break the motor circuit.

4. A speed-responsive device for controlling the operation of an electric motor comprising, 9. metal rod, means including an insulating bushing at one end of said rod to support said rod for rotation with the motor shaft and for axial movement with respect thereto, means rotatable with the motor shaft and responsive to centrifugal force for imparting axial movement to said member, two annular contacts mounted on said rod for movement therewith two relatively fixed annular contacts for cooperation with said movable contacts, said four annular contacts being disposed co-axially with said rod whereby upon axial movement of said rod said movable contacts will be parted from said fixed contacts to break the motor circuit.

5. A speed-responsive device for controlling the operation of an electric motor comprising, a metal rod, means including an insulating bushing at one end of said rod to 'support said rod for rotation with the motor shaft and for axial movement with respect thereto, means rotatable with the motor shaft and responsive to centrifugal force for imparting axial movement to said member, two annular contacts mounted on said rod for movement therewith, one of said contacts being adjacent the end of said rod opposite the bushing end, the other contact being intermediate the ends of said rod, two relatively fixed annular contacts for cooperation with said movable contacts, said four annular contacts being disposed co-axially with said rod whereby upon axial movement of said rod said movable contacts will be parted from said fixed contacts to break the motor circuit.

6. A speed-responsive device for controlling the operation of an electric motor comprising, a collar on the motor shaft, a lever pivotally supported on said collar, said lever tending to rotate on its pivot under the influence of centrifugal force, the axis of rotation of said lever being disposed transversely of the axis of said motor shaft, a leaf spring carried by said collar tending to rotate said lever in a direction to oppose centrifugal force, and switch means in the motor circuit operated by said lever.

7. A speed-responsive device for controlling the operation of an electric motor comprising, a collar on the motor shaft, a bracket secured to said collar, a lever pivoted on said bracket, said lever tendin to rotate on its pivot under the influence of centrifugal force, the axis of rotation of said lever being disposed transversely of the axis of said motor shaft, a leaf spring fulcrumed intermediate its ends on said bracket, the inner end of said leaf spring engaging said lever to urge said lever in a direction to oppose centrifugal force, means adjustable in said collar bearing against the outer end of said spring to vary the pressure exerted by said spring on said lever, and switch means in the motor circuit operated by said lever.

8. A speed-responsive device for controlling the operation of an electric motor comprising, a, collar secured to the motor shaft, a bracket on said collar, portions of said bracket being disposed outwardly from the axis of said shaft, a

member having a bearing slidable axially of the motor shaft. sald member having wing portions extending outwardly from the axis of the shaft,

interfitting finger and notch connections be' tween said wing portions and said bracket portions for transmitting rotation of said collar to said member and for permitting axial movement of said member relative to said shaft, means responsive to centrifugal force for causing axial movement of said member, and switch means in the motor circuit including an electrical contact carried by said member and movable thereby.

9. A speed-responsive device for controlling the operation of an electric motor comprising, a collar secured to the motor shaft, a bracket on said collar, a member havin a bearing slidable axially of the motor shaft, said member having portions extending outwardly from the axis of the shaft, means on said bracket engaging said portions of said member for transmitting rotation of said collar to said member and for permitting axial movement of said member relative to said shaft, means responsive to centrifugal force for causing axial movement of said member, comprising a lever pivoted on said bracket and having a, fork engagin one of said portions of said member, a spring directly engaging said lever for opposing movement of the lever under the action of centrifugal force, and switch means in the motor circuit including an electrical contact carried by said member and movable there 10. A speed-responsive device for controlling the operation of an electric motor comprising,

' a collar secured to the motor shaft, a bracketkpn said collar, a member having a bearing slidablg axially of the motor shaft, said member havin portions extending outwardly from the axis REFERENCES CITED The following references are of record in the file of this patent;

UNITED STATES PATENTS Number Name Date 424,595 Bergmann et al Apr. 1, 1890 1,000,922 Kibleck Aug. 15, 1911 1,732,367 Kleinschmidt Oct. 22, 1929 1,767,146 Lee June 24, 1930 1,840,650 Wunsch Jan. 12, 1932 2,234,124 Moody Aug. 25, 1942 Of the shaft, means on said bracket engaging said 

